Abstract:
:In a subclone derived from mouse L(tk-) cells, we found a plasmid present in a high copy number (greater than 5000 copies per cell) that was stably maintained extrachromosomally without any cytopathic effect to the host cells. This plasmid, termed L factor, has two forms: 5.3 and 5.5 kilobase pairs. DNA sequencing and restriction enzyme mapping showed that, although the structure contains DNA sequences common to polyoma virus, plasmid sequences belonging to the regulatory region (the enhancer region) and other regions are quite different from those in polyoma. In cells bearing the plasmid, we detected a low level of material that cross-reacts with antibody to polyoma tumor antigens, suggesting that the plasmids replicate and are maintained in the cells by a mechanism different from that functioning during propagation following infection of papovaviruses.
journal_name
Proc Natl Acad Sci U S Aauthors
Kusano T,Uehara H,Saito H,Segawa K,Oishi Mdoi
10.1073/pnas.84.7.1789subject
Has Abstractpub_date
1987-04-01 00:00:00pages
1789-93issue
7eissn
0027-8424issn
1091-6490journal_volume
84pub_type
杂志文章abstract::Evidence suggests that cholinergic input to the hippocampus plays an important role in learning and memory and that degeneration of cholinergic terminals in the hippocampus may contribute to the memory loss associated with Alzheimer's disease. One of the more prominent effects of cholinergic agonists on hippocampal ph...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.19.11465
更新日期:1998-09-15 00:00:00
abstract::Most studies on the ability of insect populations to transmit pathogens consider only constant temperatures and do not account for realistic daily temperature fluctuations that can impact vector-pathogen interactions. Here, we show that diurnal temperature range (DTR) affects two important parameters underlying dengue...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1101377108
更新日期:2011-05-03 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.71.8.3208
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.10.4304
更新日期:1991-05-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.7.4030
更新日期:1980-07-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.81.15.4838
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.90.6.2517
更新日期:1993-03-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Cloned DNA probes containing genes coding for the large subunit of ribulose-1,5-bisphosphate carboxylase (rbcA) of corn and of Chlamydomonas were used to identify, by heterologous hybridization, DNA fragments from Anabaena 7120 carrying the corresponding gene sequence. The same probes were used to isolate, from a reco...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1983-04-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2020-05-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.5.3133
更新日期:1981-05-01 00:00:00
abstract::Oxidative stress is a ubiquitous threat to all aerobic organisms and has been implicated in numerous pathological conditions such as cancer. Here we demonstrate a pivotal role for E2F1, a cell cycle regulatory transcription factor, in cell tolerance of oxidative stress. Cells lacking E2F1 are hypersensitive to oxidati...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1921554117
更新日期:2020-06-30 00:00:00
abstract::We and others have reported that the vast majority of virus-producing CD4(+) T cells during the acute infection of rhesus macaques with simian immunodeficiency virus (SIV) or CXCR4 (X4)-using simian/human immunodeficiency viruses (SHIVs) exhibited a nonactivated phenotype. These findings have been extended to show tha...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2009-05-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2000-07-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.96.17.9891
更新日期:1999-08-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2019-04-23 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1998-10-27 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1997-03-04 00:00:00
abstract::By using an indirect immunofluorescence technique, the distribution of poly(ADP-ribose) synthesis in human blood cells was investigated. The antibody used was reactive with poly(ADP-ribose) larger than trimers. The specific immunofluorescence of poly(ADP-ribose) synthesized in situ from NAD+ was observed in nuclei of ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.77.6.3682
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2012-01-17 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2013-11-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.81.4.1126
更新日期:1984-02-01 00:00:00